This article will discuss how long different antibiotics will stay in your body after taking them.
Getty Images / Israel Sebastian
How Long Do Antibiotics Stay in Your System?
Most antibiotics start working right after you take the first dose.
Getty Images / Israel Sebastian
Each antibiotic may stay in your body for a different amount of time, as many different classes exist.
Amoxicillin, for example, is excreted through the kidneys and urine.
Other antibiotics can stay in the body much longer.
If you have kidney problems, clearing the antibiotics from your body might take longer.
Additionally, being on a longer-term antibiotic regimen may increase the time it lasts in the body.
What Does Antibiotic Half-Life Mean?
What Other Factors Affect How Long Antibiotics Stay in the Body?
Different formulations are also available for antibiotics, which can affect absorption in the body.
Types of Antibiotics
Antibiotics can be either bactericidal or bacteriostatic.
Bactericidal antibiotics kill the bacteria, whereas bacteriostatic antibiotics prevent the growth of bacteria.
Common short-course antibiotic regimens can range anywhere from a few days to up to two weeks.
Acute infections will likely only require oral or topical antibiotic forms.
However, more severe infections may warrant intravenous (IV) antibiotics administered through the veins.
Your healthcare provider will determine your dose based on the key in of infection and antibiotic.
Dosing recommendations may also change for people with kidney problems and children.
Generally, large doses of antibiotics are not always the best form of treatment.
Antibiotic resistance triggers when the germs or bacteria fight off the drugs designed to kill or suppress them.
The likelihood of antibiotic resistance has increased rapidly due to the poor use of antibiotics.
Summary
Antibiotics will always play a crucial role in treating infections.
As with any drug, it will take some time to completely leave your body after taking it.
Talk to your healthcare provider if you have questions about your infection and antibiotic treatment.
Frequently Asked Questions
Generally, most antibiotics are safe to take on an empty stomach.
For example, you should take tetracyclines three hours before having any dairy products.
Before starting treatment, ask your healthcare provider if dairy consumption will affect your particular antibiotic.
Some antibiotics can be broken down in the liver.
Always tell your healthcare provider about all your medications before starting a new treatment.
They can inform you if any interactions are possible.
The author would like to recognize and thank Jaycob Mathew Pena for contributing to this article.
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